If your next sunshine holiday is plagued by mozzie bites, physicists have discovered why you are unlikely to know anything about it until you discover the itchy lump left behind.

The chances of detecting a mosquito in time to exact your revenge is slim because the little bloodsuckers are canny enough not to push off with their legs.

Scientists have puzzled over how the insects, often laden with two or three times their weight in blood, manage to flee undetected.

At least one species of mosquito – Anopheles coluzzii – does so by relying more on lift from its wings than push from its legs to generate the force needed to take off from a host’s skin, researchers report October 18 in the Journal of Experimental Biology.

The mosquitoes’ undetectable departure, which lets them avoid being smacked by an annoyed host, may be part of the reason A. coluzzii so effectively spreads malaria, a parasitic disease that kills hundreds of thousands of people each year.

Researchers already knew that mosquito flight is unlike that of other flies.

To find out just how different, Sofia Chang of the Animal Flight Laboratory at the University of California, Berkeley and her colleagues set up a flight arena for mosquitoes.

Using three high-speed video cameras, the researchers created computer reconstructions of the mosquitoes’ takeoff mechanisms to compare with those of fruit flies.

There is a scientific reason why you don't feel mosquitoes on your skin (Image: Library image)

Mosquitoes are as fast as fruit flies while flying away but use only about a quarter of the leg force that fruit flies typically use to push off, Chang and her colleagues found.

And 61% of a mosquito’s takeoff power comes from its wings. As a result, the mosquitoes do not generate enough force on a mammal’s skin to be detected.

“If they are so stealthy when they leave, they must be stealthy as they land, too,” said Chang, who now wants to find out whether mosquitoes land as gently as they depart.